What is HER 2 and what does it mean?
HER2 is a protein that helps breast cancer cells grow quickly. Breast cancer cells with higher than normal levels of HER2 are called HER2-positive. These cancers tend to grow and spread faster than breast cancers that are HER2-negative, but are much more likely to respond to treatment with drugs that target the HER2 protein.
All invasive breast cancers should be tested for HER2 either on the biopsy sample or when the tumor is removed with surgery.